Automatic saw-sharpening machine.



E. S. BERRY. AUTOMATIC SAW SHARPENING MACHINE. APPLIGATION FILED 111111.30. 1910.

1,049,980. Patented Jan. 7, 1913.

6 SHEETS-SHEET l.

ATTORNEYS E. S. BERRY. AUTOMATIC SAW SHARPENING MACHINE. APPLICATION FILED MAR. 30, 1910.

Patented Jan. 7, 1913.

6 SHEETS-SHEET 2.

'a F9 03 I ATTORNEYS las. BERRY. AUTOMATIC SAW SHARPENING MACHINE.

APPLICATION FILED MAR.30, 1910.

1,049,980, Patented Jan. 7, 1913.

6 SHEETS-SHEET 3.

WM; f

COLUMBIA PLANnr-RAPH C0.. WASHINGTON. D. C.

E. S. BERRY.

AUTOMATIC SAW SHARPENING MACHINE.

APPLIUATION FILED MAR.so.191o.

1,049,980. Patented Jan. '7, 1913.

6 SHEETS-SHEET 4.

ATTORNEYS coLunBm PLANQGRAPM CO..'\VASHINGTON. n. c.

E. s.. BERRY. i AUTOMATIC SAW SHARPBNING MACHINE.

APPLIGATION FILED MAR.30, 1910.

1,049,980. l Patented Jan. 7, 1913.

? Arromvfys E. S. BERRY.

AUTOMATIC SAW SHARPENING MAGHINE.

APPLICATION FILED M-AR.30, 1910.

Patented Jan. 7, 1913.

SHEETS-SHEET 6.

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WIT/VESSES:

ATTORNEYS UNITED STATES PATENT OFFICE.

ELWIN SOLOIT BERRY, OF PUTNAMVILLE, VERMONT, ASSIGNOR TO O. V. HOOKER AND SON, OF ST. JOHNSBURY, VERMONT, A CORPORATION.

AUTOMATIC SAW-SHARPENING MACHINE.

To all whom t may concern.'

Be it known that I, ELwIN S. BERRY, a citizen of the United States, and a resident of Putnamville, a village in the town of Middlesex, in the county of Vashington and State of Vermont, have invented a new and Improved Automatic Saw-Sharpening vfachine, of which the following is a full, clear, and exact description.

The object of the invention is to provide a new and improved automatic saw sharpening machine, more especially designed for grinding, sharpening or gumming the teeth of straight or circular saws, and arranged to allow running the machine at a high speed, to quickly sharpen the saw, to insure positive intermittent feeding of the saw and positive movement of the grinding wheel to and from the saw, and to reduce vibration to a minimum and thus permit accurate and uniform sharpening of the teeth of a saw.

For the purpose mentioned, use is made of a revoluble grinding wheel, adapted to move bodily in and out of grinding engagement with the saw, and a feeding device for intermittently advancing the saw a distance corresponding to the length of the tooth of a saw, the feeding movement beginning during the receding of the grinding wheel, so that the top or back of the next saw tooth is in Contact with the grinding wheel, and consequently at each operation the front and throat of a saw tooth and the back of the next following saw tooth are subjected to a grinding action.

A practical embodiment of the invention is represented in the accompanying drawings forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the views.

Figure l is a front elevation of the machine arranged for sharpening the teeth of straight saws; Fig. 2 is a side elevation of the same, parts being in section; Fig. 3 is an enlarged plan view of the same; Fig. a is a rear sectional elevation of the same on the line t-/l of Fig. 3; Fig. 5 is a front elevation of the machine, part of the driving mechanism being removed; Fig. 6 is a plan view of the machine arranged for sharpening the teeth o-f circular saws; Fig. T is a sectional front elevation of the same on the line 7-7 of Fig. 6; Fig. 8 is an enlarged plan view of part of the grinding wheel and a straight saw and its feeding device; Fig.

Specification of Letters Patent.

Application filed March 30, 1910.

Patented Jan. 7, 1913..

serial No. 552,337.

9 is an enlarged transverse section of part of the saw-feeding device. Fig. 10 is a perspective view of the saw feed device; Fig. 1l is a side elevation of an adjustable part of the main frame, one of the members being shown detached; and Fig. l2 is a sectional plan view of part of the feed device.

On the top of a suitably constructed main frame A is pivoted at B a horizontally-extending arm B, supporting bearings B2, B3, in which is mounted to turn the shaft or spindle C of a grinding wheel G, removably held on the said shaft or spindle. By imparting a swinging motion to the arm B from the right to the left, the peripheral face of the grinding wheel C is bodily moved into grinding engagement with the teeth of a saw to be sharpened, it being understood that in case the saw is a straight or band saw D, it is mounted on a support E (see Figs. l, 2, 3 and 5), and if a circular saw D is to be sharpened it is mounted on a support E (see Figs. l, 2, 3, 6 and 7), the said supports E and E being removably and adjustably held on the main frame A, as hereinafter more fully explained. The peripheral face of the grinding wheel C is shaped to engage the front and throat of a tooth of the saw D or D to be sharpened at the time (see Figs. 6 and 8) and during the time the saw D or D is at rest. A feeding device F serves to engage the saw D or D, to intermittently advance the same the distance of the length of a saw tooth, and the arrangement is such that the feeding movement begins at the time the grinding wheel C recedes from the front and throat of the saw tooth, so that the back of the next following saw toot-h is moved into grinding contact with the front beveled port-ion C2 of the grinding wheel C. rThus during each action, the front and throat of one tooth are ground and the back of the next following tooth.

On the shaft C of the grinding wheel C is secured a pulley G, connected by a belt G with a pulley G2, secured on the main driving shaftI H, provided with fast and loose pulleys H, connected by belt with other machinery, for imparting a rotary motion to the main driving shaft H, which by the pulleys G2, G and the belt G rotates the shaft C and consequently the grinding wheel C. The main driving shaft H is journaled in bearings H2, H3, of which the bearing H2 is hung on trunnions H* carried by the main frame A, so as to permit of swinging the shaft H up or down, and the bearing H3 is pivoted at one side at H5 on the main frame A, and is pressed on at its other side by a spring-pressed yoke H6, to hold the free end of the bearing H3 in contact with a lever H7, fulcrumed on the main frame A. A hand lever H2, likewise fulcrumed on the frame A (see Fig. l) engages the lever H2, so as to permit the operator having hold of the lever H2, to impart a swinging motion to he latter in the direction of the arrow a, to impart a swinging motion to the lever H2 in an opposite direct-ion, to swing the bearing H2 upward against the tension of the spring-pressed yoke H5. On the shaft H, adjacent to the bearing H5 is secured a friction pinion l, adapted to engage a friction wheel l', secured on a transversely-extending cam shaft l2, journaled in suit-able bearings on the main frame A. On the opposite faces of the wheel I are secured cams J and K, of which the cam J controls the bodily sidewise movement of the grinding wheel C, while the cam K controls the feedino device F.

it is understood that normally the pinion I is out of engagementwith the friction wheel l', but when the operator presses the lever H5 as described, the shaft H is swung upward, so as to move the friction pinion l in peripheral contact with the friction wheel I, whereby the latter is driven from the shaft H, and consequently a rotary motion is given to the cam shaft l2 and its cams J and K, in the direction of the arrow Z9 (see Fig. l).

ln order to control the sidewise movement of the grinding wheel C from the shaft H, the followingl arrangement is made: A friction roller J on on-e end of a lever J2, is adapted to be engaged by the peripheral face of the cam J (see Fig. et), and the leve r J 2 is fulcrumed on a block J3, mounted to slide up and down in a guideway A', formed on the main frame A. The lever J2 is provided with a counter-weight J* and with an' upwa-rdly-extending arm J 5, terminating in a point JG, extending into a vertically-disposed groove L, formed in the lower portion L2 of a nut L, in which screws a screw rod L5, mounted to turn in suitable bearings arranged on the top of the arm B, on which the shaft C" is journaled. The lower portion L2 of the nut L extends through a slot BL in the arm B, as plainly indicated in Figs. Z and 4, and one outer end of the screw rod L3 is provided with a lnob or a handle L'L under the control of the operator, for turning the screw rod L2, with a view to shift the nut L to the right or to the left, according to the direction in which the screw rod L2 is turned. Now by shifting the nut L, the latter acts on the arm J 5, to impart a swinging motion to the lever J2, so as to hold lt is understood that the counter-weight J 4 holds the point J G at all times in engagement with the groove L of the lower end L2 of the nut L.

The block J 3, previously mentioned, and on which the lever J2 is fulcrumed, is provided with a pin J 2, projecting into an elongated slot N of a lever N, fulcrumed at N2 on the main frame A, and provided with an upwardly-extending handle N2, provided near its upper end with a pivoted half-nut N4, adapted to engage a screw rod N5, screwing in a bearing A2 forming part of the main frame A. @ne outer end of the screw rod N5 is provided with a knob or a handle NG, under the control of the operator for turning the screw rod N5, so as to shift the handle N3 to the right or to the left, thereby imparting an up and down swinging motion to the lever N, to raise or lower the block J 2 and consequently the fulcrum for the lever J2, to cause the cam J to engage the friction roller J sooner or later, according to the depth of the tooth to be sharpened by the grinding wheel C. rI'he arm B is pressed on at its right-hand side by a spring B5, attached to a bearing A2, to normally hold the grinding wheel C out of engagement with the saw D or D', and the swinging movement of the arm B to the right is limited by a set screw BG, screwing in a bearing A3, carried by the main frame A. Now when the machine is running, the cam J imparts a swinging motion to the lever J 2, so that the arm J5 thereof acts on the nut L, and in doing so imparts a swinging motion to the arm B, to swing t-he same from the right to the left to move the grinding wheel C in grinding engagement with the front and throat of a tooth, as plainly indicated in Fig. S. During this movement of the arm B from the right to the left, the spring B5 is placed under tension, and when t-he friction roller J has passed the crown of the cam J, then a return swinging move ment of the arm ll takes place owing to the action of the spring B5, and consequently the grinding` wheel C is gradually moved out of engagement with the front and throat of the tooth.

From the foregoing it will be seen, that by the arrangement described, the grinding wheel C is moved in grinding engagement with the tooth of a saw and backv to normal position, during each revolution of the cam shaft l2.

lt is understood that on adjusting the screw rod N5, the block J is raised or lowered and with it the lever J 2, to change the latters position relative to the cam J, and by adjusting the screw rod L5, a swinging motion is imparted to the lever J 2, for changing the position of this lever relative to the cam J. By the two adjustments described, the sidewise bodily movement given to the grinding wheel C can be regulated to the minutest degree, according to the shape and location of the tooth of the saw under treatment at the time.

The cam K is a face cam and its face is engaged by a set screw K, held in the lower end of an arm K2, having a polygonal eye K3 slidingly engaging the polygonal portion O of a rock shaft O, extending lengthwise and journaled in suitable bearings arranged on brackets A4, forming part of the main frame A. On the rock shaft O is secured an upwardly-extending arm O2, pivotally connected by a link 03 with an arm 0*, pivoted at O5 on a bracket A5, forming part of the main frame A. On the arm O* is arranged a sliding block O6, carrying a vertically-disposed pivot pin F, on which is mounted to swing a head F2, provided with a rod F3, terminating in an upwardly-extending finger F4, adapted to engage one of the teeth of the saw D or D', preferably the one in front of the tooth to be sharpened by the grinding wheel C at the time. A spring F5 held on the arm O4 presses the head F2, so as to hold the finger F* in contact with the tooth and to allow sidewise swinging of the head F2, rod F3 and finger Ft, when the latter passes from one tooth to the next following one during the return stroke of the arm 04. The head F2 is held adjustably, and for this purpose a screw rod F6 is mounted to turn in the block 0 and screws in the arm O4, so as to move the head F2 in the direction of its length, to bring the finger F* in proper relation to the tooth of the saw D or D to be sharpened at the time. 1When t-he desired adjustment is made, the screw rod F6 is locked in place by a am nut F7, as plainly indicated in Fig. 9. Now when the machine is running, the cam K acts on the set screw K of the arm lf2, to impart a transverse swinging motion to the same, thus rocking the shaft O, which by the arm O2 and the link O2 imparts a transverse swinging movement to the arm 0", to cause the finger F4 to intermittently feed the saw D or D forward a distance corresponding to the length of a tooth.

1n order to aid the feeding device just described to feed saws having teeth of dierent length, the following arrangement is made: The upper' end of the arm K2 is provid-ed with a nut K4, in which screws a screw rod P, mounted to rotate in arms P and F2 attached to the ends of the rock shaft G. @n one outer end of t-he screw rod P is a hand wheel P2 under the control of the operator, to turn the screw rod P and thus shift the arm K2 lengthwise on the said screw rod, to cause the cam K to engage the set screw K sooner or later, according to the direction in which the arm' K2 is moved, by the operator turning the screw rod l). When the desired adjustment is made, the screw rod P is fastened in place in the bearing P2 by a set screw Pt.

ln o-rder to hold the set screw K in proper relation to the face of the cam K, use is made of an arm P5, depending from the rock shaft O and connected with a spring P6, attached to the main frame A (see Figs. 1, 2 and 3), to impart a rearward swinging motion to the arm K2, which rearward movement, however, is limited by an arm P7, secured to the rock shaft O and abutting against a set screw PS held on the main frame A.

The saw support E for the straight or band saw D is arranged as follows: The saw support E is in the form of a horizontally-disposed plate, provided at the side next to the grinding wheel C with a rabb-et E2 having an undercut, and extending obliquely, as plainly indicated in Fig. 3, t-he width of the rabbetbeing less than that of the saw D, so that the teeth of the saw project beyond the right-hand side of the support E for the grinding wheel C to engage the teeth of the saw, withoutdanger of cutting into th-e support E. The support E is adjustably fastened by a vertical bolt E3 to a. slotted arm AG of the bracket A5, and a horizontally-extending adjusting screw E4 screws in the rear of the said support and abuts against the arm A6, so that when the bolt E2 is loosened, the operator can swing the support E horizontally into the desired oblique posit-ion in which the support is fastened by the bolt E3 and the adjusting screw E4.

A butto-n Q is in engagement with and presses the top of the saw D opposite the tooth to be sharpened by the grinding wheel C. The button Q is held on the free end of a spring Q, clamped to the upper end of a stud Q2, adjustably secured to a slotted arm A7 of the bracket A5. A spring R presses with its free end against the points of the saw teeth to hold the saw against the undercut wall of the rabbet E2, and the said spring R is provided with a hub R (see Fig. Q), engaging the stud Q2 and secured thereto by a set screw R2. The bracket A5 which carries the lever O4 of the feed device F and the saw support E, is preferably held adjustable on the main frame A, to allow of quickly and correctly assembling the parts.

The saw support E for the circular saw D consists of a stud E5, rising from a slotted bracket E6, adjustably secured by a bolt E7 to a slotted arm AS, forming part of the main frame A. On the stud E5 is `placed a cone E2, adapted to engage the eye of the saw D, to readily center the same on the stud E5. The bracket E is provided with a rising extension E@ (see Figs. 6 and 7) forming a rest for the circular saw adjacent the stud E5 and cone ES.

The saw D adjacent the grinding wheel is supported on a support A?, forming part of an extension of the bracket n.5.

lt is understood that when a circular saw D is sharpened, the support E is removed and the spring is swung' out of the way, but use is made of the spring-pressed button C.

The operation is as follows: When` it is desired to sharpen a straight or band saw D, the latter is placed in posit-ion on the rabbet E2 of the support E, and the linger F'l is engaged with one of the teeth of the said saw. The operator now imparts a swinging motion to the lever HS in the direction of the arrow a, so that the cam shaft wheel l is rotated, as previously explained, whereby a sidewise swinging motion is given to the arm B, to move the rotating grinding wheel C in engagement with the front and throat of a tooth on the saw D. The grinding wheel C moves quickly into and out of engagement with front and throat. of the tooth of the saw, and as soon as the grinding wheel. C starts on the receding or ret-urn movement, the feeding device F is actuated by the cam K, so that the saw D is pushed rearwardly in the direction of the arrow c, whereby the back of the next following` tooth is moved in contact with the bevel face C2 of the grinding wheel C. During the linal return movement of the grinding wheel C, the feeding' of the saw D is completed, and then the feeding device F returns to its previoi'ls position, by engaging the linger ll"l with the next following tooth. As soon as the feeding of the saw D is completed, the grinding wheel C again moves into active position, to grind the front and throat of the next tooth, and the above described operation is repeated. 1llVhen it is desired to grind the teeth of a circular saw D, the support E is removed, as previously mentioned, and the circular saw is mounted on the support E', by placing the eye of the saw D in position on the stud E5 and centering the circular saw thereon by the insertion of the cone lil. The spring R used for holding the band saw D in position is preferably swung out of the way, as it is not necessary, but the spring-pressed butt-on Q is used to hold the circular saw D down on the support A) (see 5 and 7). The feeding device F is used in the same manner as previously described, that is, when the machine is ruiming the finger il engages one of the teeth of the circular' saw D, to turn the latter on the cone lds, as the center, and the grinding wheel C is bodily moved sidewise, to engage the .front and throat of recense a tooth while the saw D is at rest, and to grind the bach of the next following tooth during the receding movement of the grinding wheel C and the forward feeding of the saw D by the feeding device F.

lt is understood thatl the screw rod N5 serves to give a minute adjustment to the levers N3 and J2, and the screw rod La serves to adjust the said levers according to the diameter of the grinding wheel C used at the time, that is, for larger grinding wheels the arm B is set fart-her to the right by the use of the screw rod L3 than is required for grinding wheels C of smaller diameter.

Having thus described my invention, l claim as new and desire to secure by Let-- ters Patent:

l. An automatic saw sharpening machine, comprising a saw support, a revoluble grinding' wheel, a spring-pressed pivoted arm in which the said grinding wheel is journaled, a revoluble cam, an adjustable connection between the said cam and the said arm to periodically move the grinding wheel into grinding Contact with the saw and to allow the spring of the arm to return thel latter and the grinding wheel, a second cam rotating in unison with the said first-named cam, a pivoted pushing device for imparting an intermittent feeding motion to the saw, and an adjustable connection between the said second cam and the said pushing device.

2. An automatic saw sharpening machine comprising a saw support, a revoluble grinding wheel, a spring-pressed pivoted arm in which the said grinding wheel is journaled, a revoluble cam, an adjustable connection between the said cam and the said arm to periodically move the grinding wheel into grinding Contact with the saw and to allow the spring of the arm to return the latter and the grinding wheel, a second cam rotating in unison with the said firstnamed cam, a pivoted pushing device for imparting an intermittent feeding motion to the saw, an adjustable connection between the said second cam and the said pushing device, a main driving shaft for driving the said grinding wheel, a cam shaft carrying the said cams, and a friction drive between the said shafts.

3. An automatic saw sharpening machine comprising a saw support, a revoluble grinding wheel, a spring-pressed pivoted arm in which the said grinding wheel is journaled, a revoluble cam, an adjustable connection between the said cam and the said arm to periodically move the grinding wieel into grinding contact with the saw and to allow the spring of the arm to return the latter and the grinding wheel, second cam rotating in unison with the said firstnamed cam, a pivoted pushing device for imparting an intermittent feeding motion to the saw, an adjustable connection between the said second cam and the said pushing device, a main driving shaft, pivoted bearings for the said driving shaft, a cam shaft carrying the said cams, wheels on the said cam shaft and the said main shaft, and 1nanually-controlled means for imparting a swinging motion to one of the said main shaft bearings to move the said shaft wheels in or out of engagement.

y-l-V. An automatic saw sharpening machine provided with a saw support, means for intermittently feeding the saw, a revoluble grinding wheel for engagement with the teeth of the saw, a pivoted arm on which the said grinding wheel is journaled, a revoluble cam, a lever controlled by the said cam, means for bodily raising or lowering the said lever to change the position of the lat-ter relatively to the cam, and means for imparting a swinging motion to the said lever to adjust the same relatively to the cam.

5. An automatic saw sharpening machine provided with a saw support, a revoluble grinding wheel, a pivoted arm on which the grinding wheel is journaled, a screw rod mounted to turn on the said arm, a nut screwing on the said screw rod, a cam lever carrying the said nut, and a revoluble cam periodically engaging the said cam lever to impart a swinging motion to the said arm.

G. in automatic saw sharpening machine provided with a saw support, a revoluble grinding wheel, a pivoted arm on which the grinding wheel is journaled, a screw rod mounted to turn on the said arm, a nut screwing on the said screw rod, a cam lever engaging the said nut, a revoluble cam periodically engaging the said cam lever to impart a swinging motion to the said arm, a sliding block on which the said cam lever is fulcrumed, and manually-controlled means for shifting the said sliding block.

7. An automatic saw sharpening machine provided with a saw support, a revoluble grinding wheel, a pivoted arm on which the grinding wheel is journaled, a screw rod mounted to turn on the said arm, a nut screwing on the said screw rod, a cam lever engaging the said nut, a revoluble cam periodically engaging the said cam lever to impart a swinging motion to the said arm, and a spring connected with the said arm to return the latter.

S. An automatic saw sharpening machine provided with a saw support, a revoluble grinding wheel, a pivoted arm on which the grinding wheel is journaled, a screw rod mounted to turn on the said arm, a nut screwing on the said screw rod, a cam lever engaging the said nut, a revoluble cam periodically engaging the said cam lever to impart a swinging motion to the said arm, a

spring connected with the said arm to ret-urn the latter, and an adjustable stop for limiting the return movement of the said arm.

9. An automatic saw sharpening machine provided with a saw support, a revoluble grinding wheel, a pivoted arm on which the grinding wheel is journaled, a screw rod mounted to turn on the said arm, a nut screwing on the said screw rod, a cam lever engaging the said nut, a revoluble cam periodically engaging the said cam lever to impart a swinging motion to the said arm, a spring for returning the said arm, a sliding block on which the cam lever is pivoted, a hand lever having a connection with the said block, a pivoted half nut on the said hand lever, and a screw rod mounted to turn and on which screws the said half nut.

l0. A saw sharpening machine provided with a revoluble grinding wheel having bodily movementtoward and from the saw to be sharpened, an adjustable saw support, and a feed device for periodically advancing the saw, the feed device comprising a revoluble face cam, a rock shaft having arms, one of which is adapted to be actuated by said cam, said arm being adjustable along the shaft to cause it to be engaged by the cam sooner or later according to the direction in which the arm is moved, a link connected with the other rock shaft arm, a lever connected with the said link, a pivoted and spring pressed head adjustably mounted on the said lever, and a push bar on the said head and having a finger engaging a tooth of a saw.

11. A saw sharpening' machine provided with a revoluble grinding wheel having bodily movement toward and from the saw to be sharpened, an adjustable saw support, and a feed device for periodically advancing the saw, the feed device comprising a revolub-le face cam, a rock shaft having arms, of which `one is a cam arm and adapted to be actuated by the said cam, a link connected with the other rock shaft arm, a lever connected with the said link, a head mounted to swing on the said lever, a push bar on the said head and having a finger engaging a tooth of the saw, manually-controlled means for adjusting the said head, and manually-controlled means for shifting the said cam arm on the said rock shaft.

12. In a saw sharpening machine, a saw support having a shoulder against which the saw rests, a spring arm carrying at its free end a button for engaging the top of the saw, means for adjustably mounting the spring arm and a spring for engaging the teeth of the saw, said spring being adjustably mounted on the means for mounting the spring arm.

13. ln a saw sharpening machine, a saw support having a1 shoulder against which the saw rests, a spring arm for engaging the top of the saw, a. stud by meansI of which the arm is secured in position, a spring for engaging the teeth of the saw, Said spring having` a huh mounted on the stud, and a Screw for securing the huh of the spring in position.

14. ln a saw sharpening machine, a rook Shaft provided with a fixed arm and a slidalole arm, a cam 'for operating the shaft by meane of the sljidahle arm, a pivoted lever, a link connecting the arm of the rook Shaft Wit-h the lever, a push rod carried by the lever for engaging a SaW tooth, a nut carried hy the slidahle arm of the rock shaft, and a Screw rod Working in said nut.

15. In a saw sharpening machine, a pivoted arm, a grinding Wheel mounted in the arm, a pivoted and counterbalanced lever provided With an upwardly projecting arm, a cam with Which the lever engages, a Screw rod mounted in the said arm, and a nuton the Screw rod and With which the arm of the lever engages.

16. ln a Saw sharpening machine, a pivoted arm, a grinding Wheel mounted in the arm, a. slidulole hloclr provided with a lateral pin, a pivoted and counterbalaneed lever carried by the block and provided Wit-h an upwardly projecting arm, a cam With which the lever engages, a Screw rod mounted in the pivoted arm, a nut on. the Screw rod and with which the arm of the lever engages, and a lever provided With a Slot through which the pin of the block passes.

17. In a saw sharpening machine, a pivoted arm, a `grinding Wheel mounted in the arm, a slidahle block provided with a lat eral pin, a pivoted and counterhalanced lever carried by the block and provided with an upwardly projecting arm, a cam With which the lever engages, a screw rod mounted in the pivoted arm, a nut on the screw rod and With which the arm of the lever engages, a lever provided With a slot through which the pin of the block passes, a screw rod, and a pivoted nuton the lever and with which the screw rod engages.

18. ln a saw Sharpening machine, a swinging and revolving grinding Wheel, a Saw 'feeding device, a driving shaft, a bearing for one end of the shaft hung on trunnions, a hearing in which the other end of the shaft is mounted, pivoted at one side, a spring pressed yoke engaging the free end of said bearing, a pivoted lever engaging the yoke, a second lever engaging the firstlever, a friction pinion on one end of the driving shaft, a friet-ion Wheel With Which the pinion is adapted to engage, and means for operating the saw feeding device and Swinging the grinding Wheel from the frietion Wheel.

in testimony whereof I have Signed my name to this speciication in the presence of tivo subscribing Witnesses.

ELXVIN SOLON BERRY.

lliitnesses:

VALTER C. VVASHBURN, BURTON BAILEY.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

